#---
# Excerpted from "Metaprogramming Ruby 2",
# published by The Pragmatic Bookshelf.
# Copyrights apply to this code. It may not be used to create training material,
# courses, books, articles, and the like. Contact us if you are in doubt.
# We make no guarantees that this code is fit for any purpose.
# Visit http://www.pragmaticprogrammer.com/titles/ppmetr2 for more book information.
#---
$INHERITORS = []
class C
  def self.inherited(subclass)
    $INHERITORS << subclass
  end
end

class D < C
end

class E < C
end

class F < E
end

$INHERITORS # => [D, E, F]
